The present invention relates to a process for internally lining a conduit by bonding with a resin to the inner wall the conduit, of an inner sealed lining sleeve, by under the urging of a pressurized fluid on the inner wall of the sleeve.
Such a process is advantageous from the technical and economical points of view for preventing or repairing damage to the conduit or for obtaining a smooth inner wall and/or a wall resistant to different chemical products. The sleeve may be adapted to any configuration of the section of the conduit. Conduits of great length up to 300 m and more may be lined in this way. The cross sections of the conduits may vary from approximately 50 cm.sup.2 to sections of several m.sup.2. The conduits may be of any kind and of any material and may, for example, be conduits buried in concrete or the like.
In the known processes, since the material used for the sleeves is not resilient, the dimensions of the sleeve and particularly of its cross section must be very accurate so as to allow suitable application of the outer wall of the sleeve to the inner wall of the conduit. In known processes, either the outer wall of the sleeve or the inner wall of the conduit is coated with a resin, this resin being polymerized when the sleeve is applied against the conduit. Since the polymerization of a resin generally takes place at an optimum temperature maintained substantially constant for a given length of time, the known processes have not solved the problem of permanently controlling the temperature during the period of application of the sleeve against the conduit. Furthermore, since the sleeve (or conduit) is generally coated in situ, the thickness of the resin is not even and the adhesive application of the sleeve takes place in an uneven and inaccurate way.